fix: typo in troubleshooting.md (#1916)

## Checklist

- [x] I have ensured my pull request is not behind the main or master
branch of the original repository.
- [x] I have rebased all commits where necessary so that reviewing this
pull request can be done without having to merge it first.
- [x] I have written a commit message that passes commitlint linting.
- [x] I have ensured that my code changes pass linting tests.
- [x] I have ensured that my code changes pass unit tests.
- [x] I have described my pull request and the reasons for code changes
along with context if necessary.

Signed-off-by: WuMingDao <[email protected]>

Author: WuMingDao

docs/troubleshooting.md

@@ -11,7 +11,7 @@ consider contributing to this documentation.
 
 ## Whenever I try to access my route, it sends back a 404
 
-This is a common but troublesome problem when working with Koa middleware. First, it is critical to understand when Koa generates a 404. Koa does not care which or how much middleware was run, in many cases a 200 and 404 trigger the same number of middleware. Instead, the default status for any response is 404. The most obvious way this is changed is through `ctx.status`. However, if `ctx.body` is set when the status has not been explicitly defined (through `ctx.status`), the status is set to 200. This explains why simply setting the body results in a 200. Once the middleware is done (when the middleware and any returned promises are complete), Koa sends out the response. After that, nothing can alter the response. If it was a 404 at the time, it will be a 404 at the end, even if `ctx.status` or `ctx.body` are set afterwords.
+This is a common but troublesome problem when working with Koa middleware. First, it is critical to understand when Koa generates a 404. Koa does not care which or how much middleware was run, in many cases a 200 and 404 trigger the same number of middleware. Instead, the default status for any response is 404. The most obvious way this is changed is through `ctx.status`. However, if `ctx.body` is set when the status has not been explicitly defined (through `ctx.status`), the status is set to 200. This explains why simply setting the body results in a 200. Once the middleware is done (when the middleware and any returned promises are complete), Koa sends out the response. After that, nothing can alter the response. If it was a 404 at the time, it will be a 404 at the end, even if `ctx.status` or `ctx.body` are set afterward.
 
 Even though we now understand the basis of a 404, it might not be as clear why a 404 is generated in a specific case. This can be especially troublesome when it seems that `ctx.status` or `ctx.body` are set.